Though early reports and speculation suggested Apple's custom A4 system-on-a-chip found inside the iPad was based on the more advanced, dual-core ARM Cortex-A9 architecture, one new report says the processor actually "just isn't anything to write home about."

Citing anonymous sources, Jon Stokes of Ars Technica wrote Sunday that the A4 is a custom 1GHz system on a chip with a single Cortex-A8 CPU and a PowerVR SGX GPU. Apple has not revealed specifics on the design of its processor aside from its speed, but has touted that the A4 was designed in-house by the company for the forthcoming iPad.

"In all, the A4 is quite comparable to the other Cortex A8-based SoCs that are coming onto the market, except that the A4 has even less hardware," the report said. "The iPad doesn't have much in the way of I/O, so the A4 itself can do away with the I/O that it doesn't need. In contrast, the typical Cortex A8-based SoC has more I/O hardware than a mobile phone can use, because you never know what customers will need which interface types."

The Cortex-A8 allegedly found in the iPad is the same chip that has been in the iPhone 3GS since it debuted last June. The major difference: The iPhone 3GS chip is clocked at 600MHz, while the Apple A4 is allegedly 1GHz.

So why bother with custom silicon? By forgoing some features commonly found on other Cortex-A8 devices, Apple can likely squeeze more power out of the processor than others, Stokes said. For example, the iPad "may well be the only" Cortex-A8-based device that does not have a built-in camera, "so Apple has probably ditched some dedicated image processing blocks."

"With one 30-pin connector on the bottom and no integrated camera of any kind, the A4 needs a lot less in the way of I/O support than comparable chips that are intended for smartphones or smartbooks," he wrote. "This means that the A4 is just a GPU, a CPU, memory interface block (NAND and DDR), possibly security hardware, system hardware, and a few I/O controllers. It's lean and mean to a degree that isn't possible with an off-the-shelf SoC."

He also went on to say that it's not clear whether P.A. Semi, the fabless chip designer Apple bought in 2008 for $278 million, had a part in the design of the A4. He said if the acquisition did play a part, the most likely area would be dynamic power optimization.

"It's entirely possible that the majority of the P.A. Semi team's efforts are going not into an iPad chip, but into an SoC for the iPhone," he wrote. "Because the iPad's LCD is so large and its power draw so great relative to the other components, it's hard to imagine that the A4 gives the iPad more than a few percent battery life advantage vs. a chip like the Snapdragon -- in the grand scheme of things for a tablet device, the extra hardware that chips like the Snapdragon and the i.MX515 have on A4 probably doesn't matter a whole lot."

If true, the Ars Technica report soundly refutes a previous claim that the iPad included an ARM Cortex-A9-based CPU. Bright Side of News also incorrectly reported that the iPad had an ARM Mali 50-series GPU.

Regardless of the technology found in the A4, Apple is predicted to have spent about $1 billion to design its own custom silicon. And as noted in AppleInsider's hands-on impressions with the iPad, the processor makes even Apple's speedy iPhone 3GS seem a little slow.

Apple, which has been a licensee of the ARM architecture for years, claims the power efficiency of the chip will allow the iPad to offer users 10 hours of battery life in use, and over a month of standby.

"iPad is powered by our own custom silicon. We have an incredible group that does custom silicon at Apple," company co-founder Steve Jobs said during the company's iPad keynote. "We have a chip called A4, which is our most advanced chip we've ever done that powers the iPad. It's got the processor, the graphics, the I/O, the memory controller -- everything in this one chip, and it screams."

Techno-geeks focus on the inputs, the rest of the world focuses on the outputs. By making the A4 a mysterious black box, Apple avoids all of the noise from geekdom and focuses people's attention on the overall product.

I think the Wii analogy is perfect. Geeks refuse to buy it because they think the hardware is obsolete. The rest of the world buys it because it's fun.

Techno-geeks focus on the inputs, the rest of the world focuses on the outputs. By making the A4 a mysterious black box, Apple avoids all of the noise from geekdom and focuses people's attention on the overall product.

I think the Wii analogy is perfect. Geeks refuse to buy it because they think the hardware is obsolete. The rest of the world buys it because it's fun.

Very good analogy. However, the Wii is becoming obsolete because it is the same SKU that's been on shelves since 2006. It's unique and appeals to certain Family/Old Folks demographic, but even a good product can't stand up to a world of fast moving, frequently updated technology.

5 years ago most people did not have HDTVs. Now, Most Do. Huge difference. The XBox 360 with HD output started out as very very niche, now it is standard.

I think its safe to say that the average 2010 uninformed consumer who has an HDTV and picks up a Wii will be somewhat disappointed when they see the analog resolution.

Nintendo just needs to quietly refresh the hardware with HDMI output. That's all, they don't really need to change a thing.

The MacBooks are intended for the younger market, the MacBook Pro is intended for the more mature market.

Apple introduces a line of iPads, but it's not ready for market yet. As soon as sales pick up all Apple has to do is eliminate the one remaining white MacBook model as it already phased out the other MacBook models.

The iPad is intended to replace Apple's traditional computers in the younger market.

Why is this bad? Because the iPad is a closed device and doesn't encourage as much immediate hacking and interest as a open device does.

On a Mac, anyone who has the interest can fire up Terminal, learn a few Unix commands and be messing around. It encourages that because it's a open device.

The iPad has a high barrier to cross before one can get under the hood. This high barrier is going to discourage future youth from a interest in computers.

So why bother with custom silicon? By forgoing some features commonly found on other Cortex-A8 devices, Apple can likely squeeze more power out of the processor than others

There's also economies of scale at play here. If you own the chip design, you can directly benefit from any drops in production costs further down the line. Consoles have chip designs owned by the manufacturer for this very reason, and hence their ability to continuously drop the hardware price.

If the iPad is going to sell in the tens of millions then owning the chip design makes a lot of sense.

Having said that, I thinking I'm going to hold off until the 2nd gen iPad is released. I bought an 1st gen iPod touch and regretted it. The later models solved all of the iPod touch's short-comings and I fully expect the iPad to follow a similar path.

I'd love to see you try to explain why Apple's A4 chip, of which you have no knowledge, is capable/incapable of driving Apple's next take on multi-tasking in 4.0? (of which you also have no knowledge)

Current jailbroken iPhones can use Backgrounder, a feature that enables per-diem multi-tasking, with almost no impact on performance. Only battery life, which is a no-brainer/to-be-expected.

The 3GS has enough horsepower and RAM to run two apps at once with no noticeable drop in performance.

So where is the validity that a better and faster chip wouldn't be capable of what the current much slower chip already is?

LOL, so you think there is going to be true multitasking when:

-the iPad will be running the same OS as the iPhone so there will be no significant differences between the two devices

-the iPad has to power a higher res display

-the iPad will introduce more powerful apps that will be more resource intensive

If that was your argument then you are making a lousy one. The 3GS is a meaningless argument. There will not be a situation where the iPhone will have multitasking and the iPad won't. Chances are it will 've some kind of gimped, widget based where certain kinds of apps can be run in the background without the full UI being launched.

BTW, don't go off immediately saying that I don't what's inside the chip when the first two words I posted were "if true".

Very good analogy. However, the Wii is becoming obsolete because it is the same SKU that's been on shelves since 2006. It's unique and appeals to certain Family/Old Folks demographic, but even a good product can't stand up to a world of fast moving, frequently updated technology.

5 years ago most people did not have HDTVs. Now, Most Do. Huge difference. The XBox 360 with HD output started out as very very niche, now it is standard.

I think its safe to say that the average 2010 uninformed consumer who has an HDTV and picks up a Wii will be somewhat disappointed when they see the analog resolution.

Nintendo just needs to quietly refresh the hardware with HDMI output. That's all, they don't really need to change a thing.

I have my Wii hooked up to a 50" HDTV using the component cables, and it looks fine to me. I realize that the resolution isn't HD, but the aspect ratio is 16:9, and I think that's what most people notice. I agree that they should add HDMI support, but mostly because it's more convenient to plug in a single HDMI cable than component cables and a separate audio cable.

I guess I don't disagree that Nintendo should bump up the hardware spec at some point, I just think that they should (and clearly do) recognize that the marginal benefit of more pixels and fancier graphics is low, and so they should only add those things when the marginal cost is also low. We are reaching a point where it would be fairly cheap to add 720p and a faster CPU/GPU, so we probably are nearing the point where Nintendo will do that.

Regarding the demographics... the breadth of appeal for this device really is remarkable. I was at a family gathering this past weekend and everyone from toddlers to grandparents (and every generation in between) has played on a Wii and really enjoyed it (and I'd say a majority of people in the room owned one). Apple and Nintendo are wise to cast a broad net like this and eschew the techno-geeks.

The MacBooks are intended for the younger market, the MacBook Pro is intended for the more mature market.

Nonsense. MacBook models are not delineated by age in any way.

Quote:

Apple introduces a line of iPads, but it's not ready for market yet. As soon as sales pick up all Apple has to do is eliminate the one remaining white MacBook model as it already phased out the other MacBook models.

Nonsense. Why would they do that? Why would they close off an entire revenue stream?

Quote:

The iPad is intended to replace Apple's traditional computers in the younger market.

Nonsense. See first point above. Where do you even get that idea from, apart from pulling it out of your a**?

Quote:

Why is this bad? Because the iPad is a closed device and doesn't encourage as much immediate hacking and interest as a open device does.

Nonsense. It's a media delivery device, and that's what it does. Why would anyone outside of the idiot jailbreaking community want to hack it?

Quote:

On a Mac, anyone who has the interest can fire up Terminal, learn a few Unix commands and be messing around. It encourages that because it's a open device.

Nonsense. How many non-technical users do you think start "messing around" in terminal?

Quote:

The iPad has a high barrier to cross before one can get under the hood. This high barrier is going to discourage future youth from a interest in computers.

And more nonsense. You're using nonsense to explain nonsense. I would imagine (and my anecdotal theories carry as much weight as yours) iPad users are likely to already HAVE a computer.

Clearly you don't have children. My daughter was using a notebook at the age of ten so how young is a younger market? Schools these days have full computer labs and kids these days are doing Powerpoint presentations at 12 years old.

The iPad can even come close to replacing traditional computers because it doesn't run a tradtional OS, its running a mobile OS.

Even if put iWorks on it which about 1% of the market uses the iPad has little to no function for even young users. At least no more then their iPod Touch.

Perhaps "young" doesn't capture the demographic Apple is targeting with the iPad.

I can't think of a simple short term, but clearly Apple is aiming to target people
who are less comfortable with the complexities of the modern PC.
Mind you, that would certainly be more than half of the world population.

I would also think that the distinction between mobile OS and "traditional" OS is less relevant here, seeing as how the iPhone OS and Mac OS X they have more or less the same underlying capabilities.
Apple dictates what it can and can't do, the OS doesn't.

Everyone should be reminded that the iPad will not replace PCs and Macs.
That's not what Steve said!
It will kick ass in other regards.

The MacBooks are intended for the younger market, the MacBook Pro is intended for the more mature market.

Apple introduces a line of iPads, but it's not ready for market yet. As soon as sales pick up all Apple has to do is eliminate the one remaining white MacBook model as it already phased out the other MacBook models.

The iPad is intended to replace Apple's traditional computers in the younger market.

Why is this bad? Because the iPad is a closed device and doesn't encourage as much immediate hacking and interest as a open device does.

On a Mac, anyone who has the interest can fire up Terminal, learn a few Unix commands and be messing around. It encourages that because it's a open device.

The iPad has a high barrier to cross before one can get under the hood. This high barrier is going to discourage future youth from a interest in computers.

Wow...that's adding 2 and 2 and getting 128.

The iPad might replace the MB for K-12 but not as likely for college students.

The desire to write your own app is likely LARGER for the iPhone/iPod Touch/iPad family than it ever was for Mac OSX.

I don't even fire up terminal. I stay the hell away even as an old unix weenie. Unix command line is soooo 19th century.

If true, I hope the A4 does not make it into the next iPhone. With the iPad potentially running a year old processor, I guess the prospects of multitasking in OS 4.0 is looking pretty dim.

This is the wrong attitude. Having a stock engine that is faster isn't necessarily faster nor more efficient than one that is tuned for a specific use. Going with the A8 as their first run would have given PA Semi more time to perfect the chip. In future they'll be able to speed up the process with newer processors.

But what does it ultimately matter if it serves its purpose?

Quote:

Originally Posted by mark2005

If true, the A4 is running at least 67% faster than the CPU in the 3GS. Why wouldn't that make any difference?

I'd think they'd underclock it. I think going 33% faster clock speed at 800MHz with an optimized chip with PA Semi power management might be the most we'd see with the next iPhone. Going too fast might not give you a worthwhile product to sell the next time. Plus, getting a little more power out of it is always good for the these devices and not something we expect to increase rapidly, just not decrease.

Quote:

Originally Posted by Curmudgeon

Perhaps it's just a number too big for my brain to comprehend, but a billion dollars to essentially rejigger existing chips seems excessive.

I think $1B is cheap. The buyout was over a quarter of that cost before they ever started doing anything. Plus, that is a rumoured cost. It could easily be more or less depending on the level Apple took it to.

Quote:

Originally Posted by hexor

Who cares. If the device runs fast enough for its intended use I wouldn't care if there are a bunch of nano guinea pigs in there running the thing.

Word! Same goes for the name. If it does what I need it to do for a cost I find reasonable then nothing else is relevant.

Quote:

Originally Posted by Woohoo!

The MacBooks are intended for the younger market, the MacBook Pro is intended for the more mature market.
[...]
The iPad is intended to replace Apple's traditional computers in the younger market.
[...]
The iPad has a high barrier to cross before one can get under the hood. This high barrier is going to discourage future youth from a interest in computers.

I don't think any of that is true. The MB is an entry level machine with no age barrier, just a usage and financial barrier. The iPad is clearly an accessory device, not a Mac replacement and like the other "halo" devices it could very well lead to more Mac sales as it increases Mac interest as a whole after using the more easily had "halo devices".

Macs aren't going anywhere but up. I would not be surprised to see a 15" MB after Apple gets the plastic unibody worked out.

Quote:

Originally Posted by str1f3

LOL, so you think there is going to be true multitasking when:

-the iPad will be running the same OS as the iPhone so there will be no significant differences between the two devices

-the iPad has to power a higher res display

-the iPad will introduce more powerful apps that will be more resource intensive

Absolutely! Both devices already do multitask and we know the 3GS has the resources for backgrounding user selected App Store apps. That doesn't resolve the logistical issues for Apple as creating a task manager or app killer app is not an ideal solution for backgrounding, but the HW is more than capable.

Dick Applebaum on whether the iPad is a personal computer: "BTW, I am posting this from my iPad pc while sitting on the throne... personal enough for you?"

Why do they think the A4 would strip out camera functionality? Would Apple really design a chip just for the iPad 1.0 with anticipated sales numbers somewhere south of 12MM units? I would think that they need to sell at least 40MM A4 processors to recoup any investment they made in the design, if the $1B number is accurate within an order of magnitude. It might make sense if they just invested $100MM, but then it is still an expensive exercise.

I think it would be more appropriate to say, "pseudo-techno-geeks." -- i.e., those who pretend to themselves that they know what they are talking about, but don't really understand technology or what the iPad is at all. The iPad is an excellent litmus test.

I think it would be more appropriate to say, "pseudo-techno-geeks." -- i.e., those who pretend to themselves that they know what they are talking about, but don't really understand technology or what the iPad is at all. The iPad is an excellent litmus test.

If not, then you clearly do not understand the concept of fragmentation. They all run on the same OS, have similar interface. This is the opposite of fragmentation. It is the unification of OS across devices of that meet a variety of user needs.

Developers can code once, and it will run on all 3 platforms. If they use the proper procedures for display designs, then they can even supply a single code base for all three devices. If they want a totally different display for the the larger iPad, they still can keep all the driving logic and other non-display code without change.

Android has fragmentation because they have multiple OSes across on type of device (phones) that are incompatible. The smartphone industry as a whole has fragmentation because they have so many competing OSes. That is fragmentation.

Perhaps "young" doesn't capture the demographic Apple is targeting with the iPad.

I can't think of a simple short term, but clearly Apple is aiming to target people
who are less comfortable with the complexities of the modern PC.
Mind you, that would certainly be more than half of the world population.

I would also think that the distinction between mobile OS and "traditional" OS is less relevant here, seeing as how the iPhone OS and Mac OS X they have more or less the same underlying capabilities.
Apple dictates what it can and can't do, the OS doesn't.

Everyone should be reminded that the iPad will not replace PCs and Macs.
That's not what Steve said!
It will kick ass in other regards.

It will kick ass, but not because Apple is targeting people who are less comfortable with the complexities of the modern PC.

The message of January 27th was the form factor. The form factor will overlay different demographics as a content delivery device, not a general purpose computer. There is a difference and a large one at that.

Who knows what the chip can do. I imagine we will have more information after it is released. Even if it uses a Cortex-A8, who knows how many execution units it has in its GPU. If you think about it, why does a media device need out-of-order execution units that the Cortex-A9 has when it is probably mostly doing SIMD stuff. Maybe they are using all that extra die space for something magic (or just a bunch of SIMD execution units like the Sony Cell). You need to remember that Apple controls the Darwin Kernel and the compiler (through the LLVM project). They may have created some incredible optimizations in hardware by working with their software guys. It could have Obj-C runtime acceleration for all we know. Considering Apple just released the Grand Central Dispatch and Closures in C, they are certainly thinking about making radical changes at that level. Apple has some very smart people working in this area. My guess is that if they went to the trouble of making custom silicon, they are doing "something" radically different. I love Ars microprocessor reviews, so I hope they have the full run down (as usual) when it is released.

BTW, I love this quote from the article:
I don't know the answer to these questions, but given what I do know about the A4, I suspect that the reason is twofold. First—and this is purely my supposition—Steve Jobs just loves secrets. The A4 no doubt gives him that special, "I have my very own custom SoC that you don't know anything about" feeling, and if we're honest with ourselves, wouldn't we all love to know what it's like to have that feeling? I know I would.

Disappointing...Its still faster than the iPhone processor due to clockspeed increases, but an The A9's provide an enormous benefit, they are out-of-order processors for one, which is a MASSIVE benefit in itself, and for two they are either dual or quad cores. I cant remember who's specific test it was, but the A9 kept toe-to-toe with Intel's Atom (pinetrail) while consuming so much less power. The A9 would have been a screamer, the A8 is meh.

Apple will still market it as the god of all mobile devices though, which has me worried. I've already heard people say they want to replace their laptops with one, thinking it has all the same functionality. Those people are in for a big let-down.

It may be so or --- absolutely evenly --- it may not, too.
The fact "tech" blogger has managed to figure out block diagrams and I/O nomenclature of modern SoC (Freescale i.MX51) doesn't necessarily mean anything to A4 processor.

We mean Apple no harm.

People are lovers, basically. -- Engadget livebloggers at the iPad mini event.